Air mixer



Feb. 18, '1930. w. c. BREWER 1,747,573

AIR MIXER Filed Feb. 25, 1928 i UU! U 2% attozmn Patented Feb. 18, 1930 WILLIAM C. BREWER, OF TOLEDO, OHIO AIR MIXER Application filed February 25, 1928.

This invention relates to combustion promotion.

This invention has utility as an air prewarmer accessory for ready installation, more particularly in stoves or furnaces.

Referring to the drawings:

Fig. 1 is a fragmentary front view of a furnace having an embodiment of the invention incorporated therewith;

Fig. 2 is a section on the line Il-I, Fig. 1, on an enlarged scale;

Fig. 3 is a fragmentary view from the right "of Fig. 2;

Fig. 4 is a section on the line IKT-IV, ,15 Fig. 3;

Fig. 5 is a section on the line V-V, Fig. 4; and

Fig. 6 is a section on the line VI-VI, Fig. 2.

Furnace 1 is shown as having grate 2 with combustion chamber 3 having stoking opening 4 to be closed by lire door 5 having draft opening 6 therein to be cut olf by slide or damper 7 This door is shown as having a heat resisting bach` 8 with openings 9 therethrough to disseminate the air supply as pass ing through the openings 6 into the combustion chamber 3 for checking the furnace operation. Hereunder the function of these openings 6 through the door are radically changed with increased eciency in furnace operation. To this end, the openings 6'are left clear of cutting out by slide 7 or the slide 7 may be removed.

Insulation sheet 10 may be assembled against the back plate 8 on the combustion chamber side say by water glass to have central opening 11. of this insulation centrally of the door 5. The peripheral series of open- 0 ings 9 through the back plate 8 are accordingly closed.

Bolts 12 having threaded portions 13 may be thrust through the back platek 8 to protrude inward as aready assembly for engaging slots 14 in anges 15 of the air prewarmer device hereunder. This air prewarmer device is shown as comprising opposing end sections 16 providing return bend portions 17 as seats into which may be thrust free ends 18 of intermediate partition-provid- Serial No.A 256,863.

ing means herein shown as comprising U- shaped intermediate portion 19 terminating in outwardly extending anges 2O toward the door back. This U-shaped portion between the upper and lower legs of the U has sinuous partition-providing member 21 therein having anchor means 22 for intermediate portions thereof, with interlock. 23 for the terminal toward the door back. There is accordingly provided, at the door back, chamber 24 in communication by perforations 25 with cham.- ber 26 having communication by openings 27 with chamber 28 having communication by openings 29 with chamber 30 which has discharge by perforations or openings`31 into the combustion chamber 3. There is accordingly provided herein in series a plurality of chambers having subdivided communication means due to the perforations when the device is assembled.y

The assembly occurs by drawing the opposing end sections 16 toward each other' with U-bolt 32 and wing nuts 33 thereon coacting against clamp plate or washer 34. This simple assembly of the prewarmer device may be mounted to have slots 14 of the end section flanges 15 supported by the bolts 12 having wing nuts 35 thereon thus mounting the insulation opening 11 to register with the chamber 24 of the prewarmer device.

In practice this device is advantageously made of sheet metal of good conducting properties as copper. Furthermore, in the swinging of the door from closed position, the device is of a size not to strike the lire door frame. The location of the prewarmer device as to its inward projection is over the fire or fuel region within the combustion chamber 3. The conductivity of this device,

due to the tortuous multi-chamber passage,

Vquickly brings the air temperature upward with resultant air expansion to increase its volume, as much as twice, in many instancesV of practice. Y v

This is an automatically controlled induced draft device for supplying the prewarmed air in the promotion of combustion in the 1 combustion chamber. The perforations 25, 27, 29, 31 gradually increase in total area toward the chamber 3. There is thus provision to take care of the expansion of tlie'air due to heating with approximation of uniform rate for the automatic draft control according to the` forcing rate for the furnace. This is v 5 eifective as an automatic replenishment of Yair inquantity for complete combustion even in low grade fuel oil installations as well as in installations using coal and gas. There is economy of as much as Vtwenty per cent to forty per |cent in the use of fuel resultant from this readily applied device.

Vhat is claimed and it is desired to secure i by Letters Patent is: l

` 1. A combustion promotion device .com-r prisiiig a housing havingan intake opening at one'end and a delivery opening at the .other end', and an additional vsinuous sheet metal partition member insertable into the housing and providing with the housing a plurality of chambers in series between said openings."

2. A combustion promotion device comprising a housing having an intake opening at one end and a delivery opening at the H other end, and an additional sinuous sheet jmetal partition member insertable into the housing and providing with the housing a plurality of chambersin series between said openings, there being port means between Y the different chambers in said series, said port means being vin the partition member.

3. AA lire door having a perforate back and a draft opening ythrough the door, an annular insulation 'sheet for closing a peripheralu portion of the perforations of the i door back, a anged 'device against the ysheet having ahousing extending to a delivery Y y opening remote from the door and an additional sinuous sheet metal partition strip 'V410' insertable into the housing and providing with the housing a plurality of chambers in series .between the openings7 and bolts through the device flanges and perforate 1doorback to clamp the insulation sheet in 445 position for anchoring the device toproject rearwardly from the door. v In lwitness whereof I afliX my signature.

WILLIAM C. v 

